An ion implantation may be performed to implant ions into a predetermined region of a substrate in a manufacturing process of a semiconductor device or a flat panel display. For example, an ion implantation may be performed to form source/drain regions at surface portions of a semiconductor substrate in a semiconductor manufacturing process.
An apparatus for performing the ion implantation process, i.e., an ion implanter, includes an ion generator for ionizing a source gas, an ion extractor for extracting ions from the ion generator, a mass spectrometer for selecting desired ions among the extracted ions, an accelerator for accelerating the selected ions so as to have a predetermined amount of energy and thereby forming an ion beam, an ion deflector for adjusting the direction of the ion beam so that the ion beam scans a surface of a substrate, which is disposed in a process chamber, a support for supporting the substrate, etc.
In the ion implanter, impurities, for example, particles produced by collision between the ions and the substrate and ions which are not implanted into the substrate but scattered in the process chamber, may be attached to an inner wall of the process chamber. The attached impurities may serve as a contamination source. That is, the impurities may be separated from the inner wall and may contaminate the substrate. Thus, a cleaning process on the inner wall may be performed to remove the attached impurities. As a result, the time required to perform the ion implantation process may be increased, thereby deteriorating the efficiency of the ion implantation process.
To solve the above-described problems, a ceramic spray-coating layer may be formed on the inner wall of the process chamber. The ceramic spray-coating layer may include aluminum oxide (Al2O3) or yttrium oxide (Y2O3). The ceramic spray-coating layer may be formed to allow the impurities to be easily adsorbed thereto.
However, the ceramic spray-coating layer may be easily corroded by the adsorbed impurities, another impurities including aluminum or yttrium may be produced from the corroded ceramic spray-coating layer. As a result, the substrate may be contaminated by the impurities including aluminum or yttrium. Further, because the ceramic spray-coating layer has relatively high surface resistance, electric arcing may occur during the ion implantation process.